Experiments on baits for rats

Press, Volume CX, Issue 32460, 21 November 1970, Page 1

Experiments on baits for rats

Experiments with baits that would kill rats jn Christchurch sewers instantly would be undertaken with the co-operation of the Christchurch Drainage Board, said the chief City Health Inspector (Mr A. P. Millthorpe) yesterday.

“We have proved that rats have infested the sewers at a consistent level throughout the system,” he said. Ironically, improvements to the sewer system by way of relief trunks had led to the rise in the number of rats in the sewers, Mr Millthorpe said. Periodically, the sewers used to flood, either drowning the rats or forcing them out of the system. "The lower level, with no flooding, means that the rats find more food and are in no danger,” he said.

in public places, such as the riverbanks, and with the cooperation of property owners instituted block extermination.”

He said that, by and large, owners and occupiers of premises saw that it was in their own and the public interest to get rid of rats, and that it had to be done by the block method, as haphazard poisoning and trapping only moved rats away from buildings where the drive was on, into adjacent buildings. It had cost some firms, in older, larger buildings, thousands of dollars to get rid of rats, said Mr Millthorpe. The council team of four—but reduced to two at present because of a shortage of staff —inspected buildings in the city centre at least once in 12 to 18 months. SYSTEM SUCCESSFUL It was apparent that the systematic campaign against rats was being kept up and was successful. Destroying rats in the sewers would block a source of surface rat infestation. Mr Millthorpe said that the pest control team would be occupied in the coming months with tracing places were flies bred in the suburbs, as well as the city centre. In the past, householders had co-operated well with the team. Nobody had had to be prosecuted for not taking remedial measures.

The degree of infestation in the sewers was not serious—he' would have been extremely surprised to have found no rats with the bait testing, Mr Millthorpe said. But the tests showed that it was time the problem was dealt • with in a systematic way. SURFACE INFESTATION Mr Millthorpe said that surface rat infestation in the city had been brought down to a most satisfactorily low level by a team of four City Council pest controllers working on a block extermination system over the last five years or so. “About six years ago, it was found that the rat infestation level was surprisingly high, particularly in the commercial centre of Christchurch,” Mr Millthorpe said. “The couhcilbegan a systematic rat extermination drive